On biomass, EPA should follow the science

In fact, it stretches back to the time of cavemen. Power companies are burning trees to produce energy, a deeply misguided practice that's razing precious forests, producing fuel dirtier than coal and boosting carbon pollution right when we need to sharply curb this key contributor to climate change.

Power plants here and abroad are ramping up use of this antiquated energy source based on faulty claims that it's renewable without acknowledging its impacts on our resources and climate.

Fortunately, the U.S. Environmental Protection Agency is taking a close look at burning biomass. It should — in keeping with the President Obama's comprehensive climate action plan — rein it in.

Last fall, I joined 40 U.S. scientists in sending a letter to the Environmental Protection Agency urging the agency to follow the science on biomass and draft strong standards curbing its climate emissions. Today, 50 additional scientists have joined us in this call.

Here's why: In search of alternatives to coal and other fossil fuels, power companies have started to switch to burning biomass, plant material ranging from wood to agricultural residues to energy crops. Increasingly, they are producing electricity from wood pellets manufactured from whole trees. This is putting our Southeastern forests at grave risk.

Biomass has all too often been labeled "carbon neutral." But it's not. Scientific advances in calculating emissions make clear that burning whole trees for electricity creates more carbon pollution than coal. Carbon pollution is what's causing the changes we're already seeing in our climate through more extreme weather, storms and floods.

Burning biomass is worse than coal for several reasons. First, U.S. forests absorb a lot of carbon, more than 13 percent of our annual climate emissions each year. When you cut these forests and diminish this carbon absorption, it's the same as a net increase in carbon emissions.

Second, when trees are cut and burned to produce electricity, the carbon they've stored over many years is released immediately into the atmosphere, canceling all the good they've done. Third, wood is less energy dense than coal, so power plants have to burn more of it. That's extra carbon in the atmosphere to make the same amount of electricity.

On top of that, we're threatening our country's most biologically rich and unique forests to fuel this industry.

In July 2011, the EPA deferred permitting requirements for large power plants burning biomass to pursue a science-driven approach that would accurately quantify biomass carbon emissions. The agency empanelled a science advisory board to review the science on this issue and make recommendations for how to proceed.

In its final report, the science panel rejected the assumption of carbon neutrality for biomass, emphasizing a need for the EPA to distinguish among different biomass types and rigorously assess their life-cycle carbon impacts when used for energy production.

The EPA took the right step by seeking scientific input. Now, with the permit deferral expiring this summer, the agency should embrace the key findings of its science panel, which echo the views of scientists across the country.

Power companies should not be allowed to pollute our atmosphere and contribute to the clear-cutting of our forests while invoking claims of clean energy. The EPA must move to incentivize low-carbon biomass, such as residues from sustainable forestry operations and dedicated energy crops like switchgrass, not the carbon-intensive burning of whole trees.

The EPA has an important opportunity to issue science-grounded policies. It should avoid setting aside the science it sought by putting forth weak standards that could distort the marketplace toward greater use of unsustainable biomass. This could have significant risks to our climate, our forests and the valuable services they provide and we rely on.

Schlesinger is the president of the Cary Institute of Ecosystem Studies and former dean of the Nicholas School of the Environment and Earth Sciences at Duke University. For the last 30 years he has investigated the link between environmental chemistry and global climate change.